金属热处理 ›› 2022, Vol. 47 ›› Issue (6): 64-68.DOI: 10.13251/j.issn.0254-6051.2022.06.011

• 工艺研究 • 上一篇    下一篇

预拉伸变形量对2050铝锂合金组织和性能的影响

于娟1, 冯朝辉1, 赵唯一1, 姚勇2, 游文2   

  1. 1.中国航发北京航空材料研究院 北京市先进铝合金材料及应用工程技术研究中心, 北京 100095;
    2.西南铝业(集团)有限责任公司 铝锂合金材料研究室, 重庆 401326
  • 收稿日期:2022-02-13 修回日期:2022-04-15 出版日期:2022-06-25 发布日期:2022-07-05
  • 通讯作者: 冯朝辉,研究员,硕士,E-mail:zhaohuifeng@163.com
  • 作者简介:于娟(1988—),女,工程师,博士,主要研究方向为铝锂合金应用,E-mail:342014715@qq.com。

Effect of pre-stretching amount on microstructure and properties of 2050 Al-Li alloy

Yu Juan1, Feng Zhaohui1, Zhao Weiyi1, Yao Yong2, You Wen2   

  1. 1. Beijing Engineering Research Center of Advanced Aluminum Alloys and Applications, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China;
    2. Laboratory of Aluminum-Lithium Alloys Materials, Southwest Aluminum(group) Co., Ltd., Chongqing 401326, China
  • Received:2022-02-13 Revised:2022-04-15 Online:2022-06-25 Published:2022-07-05

摘要: 通过拉伸试验、晶间腐蚀试验以及透射电镜(TEM)等方法对固溶处理后不同预拉伸变形量处理并人工时效后2050铝锂合金厚板室温拉伸性能、抗晶间腐蚀性能以及合金的微观组织形貌进行了研究。结果表明,随预拉伸变形量的增加,合金L向和LT向的屈服强度和抗拉强度逐渐增大,变形量>4.0%后趋于平稳,伸长率逐渐降低后趋于稳定;随预拉伸变形量增加,腐蚀形貌由晶间腐蚀变为点蚀,点蚀深度逐渐减小。预拉伸变形促进了人工时效过程中晶内T1相的弥散析出,降低了晶界处T1相含量,因此提高了合金的强度和抗晶间腐蚀性能。预拉伸变形量为5.0%时,合金的强度和抗晶间腐蚀性能最佳。

关键词: 2050铝锂合金, 预拉伸变形, 拉伸性能, 抗晶间腐蚀, T1

Abstract: Effect of pre-stretching processing after solution treatment on tensile properties, intergranular corrosion resistance and microstructure of the artificial aged 2050 Al-Li alloy were studied by means of tensile test, intergranular corrosion test and transmission electron microscope(TEM). The results show that the yield strength and ultimate tensile strength at L and LT directions of the 2050 Al-Li alloy increase gradually with the increase of pre-stretching amount, and tend to be stable when the pre-stretching amount is over 4.0%, elongation decreases rapidly at first and then finally keep stable. With the increase of pre-stretching amount, the corrosion morphology changes from intergranular corrosion to pitting, and the pitting depth decreases gradually. The pre-stretching processing promotes the T1 phase precipitation in the grains and makes its distribution more dispersive and homogeneous, while the precipitation at grain boundary is restrained during the artificial aging, which consequently improves the tensile strength and the intergranular corrosion resistance. When the pre-stretching amount is 5.0%, the optimum tensile strength and intergranular corrosion resistance is obtained for the alloy.

Key words: 2050 Al-Li alloy, pre-stretching, tensile properties, intergranular corrosion resistance, T1 phase

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